#pragma once 

#include <iostream>
#include <cstdlib>
#include <cstring>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <pthread.h>
#include "log.hpp"
#include <unistd.h>

#define PORT 8081
#define BackLog 5

class TcpServer{
  private:
    int _port;
    int _listen_sock;
    static TcpServer* svr;
  private:
    TcpServer()
      :_port(PORT),
      _listen_sock(-1)
  {}
   TcpServer(const TcpServer &s)
   {}
   TcpServer(int port)
     :_port(port),
     _listen_sock(-1)
  {}
  public:
  
    static TcpServer* getinstance(int port)
    {
      static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
      if (nullptr == svr)
      {
        pthread_mutex_lock(&lock);
        if(nullptr == svr)
        {
          svr = new TcpServer(port);
          svr->InitSever();
        }
        pthread_mutex_unlock(&lock);
      }
      return svr;
    }
    void InitSever()
    {
      Socket();
      Bind();
      Listen();
      LOG(INFO , "Init success!");
    }
    void Socket()
    {
      _listen_sock = socket(AF_INET,SOCK_STREAM,0);
      if(_listen_sock < 0)
      {
        LOG(FATAL , "socket error!");
        exit(1);
      }

      // 地址复用 防止突然断开连接 不能立刻复用端口
      int opt = 1;
      setsockopt(_listen_sock,SOL_SOCKET,SO_REUSEADDR,&opt , sizeof(opt));
      LOG(INFO , "create socket success!");
    }
    void Bind()
    {
      struct sockaddr_in local;
      memset(&local , 0 ,sizeof(local));
      local.sin_family = AF_INET;
      local.sin_port = htons(_port);
      local.sin_addr.s_addr = INADDR_ANY; // 不能直接绑定公网IP
      if(bind(_listen_sock , (struct sockaddr*)&local , sizeof(local))<0){
        LOG(FATAL , "bind error!");
        exit(2);
      }
        LOG(INFO , "bind socket success!");
    }
    void Listen()
    {
      if(listen(_listen_sock,BackLog) < 0)
      {
        LOG(FATAL , "listen error!");
        exit(3);
      }
        LOG(INFO , "listen socket success!");
    }

    int Sock()
    {
      return _listen_sock;
    }
    ~TcpServer()
    {
      if(_listen_sock >= 0)
      {
        close(_listen_sock);
      }
    }
};

TcpServer* TcpServer::svr = nullptr;
